The goalkeeper makes the switch to the Academy Stadium from fellow Barclays Women’s Super League side Everton and will wear the No.22 shirt for the upcoming 2022/23 campaign.
The 24-year-old enters her second spell with City, having been part of our Academy in 2015.
Speaking about her move, she said: “I’m really happy to be back here, this time as a professional player – Manchester City is a world class club across the board, and I’m very much looking forward to being a part of that.
“I feel like it’s really important at this time in my career to take my game to the next level and being able to train and learn from the world-class players and coaches here will help me to do that.
“It’s a really ambitious club who aspire to win trophies on a regular basis, and that’s something I’m excited to be involved in over the coming seasons.”
In 2016, after a year with City, she moved to the United States on a soccer scholarship with Clemson Tigers and went on to establish herself as the team’s first choice shot stopper during her three years in the Atlantic Coast Conference.
MacIver re-joined Everton following her graduation from Clemson University in January 2020 and made her professional debut just weeks later.
She was named Player of the Match in the 2020 Women’s FA Cup Final against City at Wembley Stadium, with Gareth Taylor’s side running out 3-1 winners after extra time.
The keeper has represented England at various youth levels from Under-17s upwards before she was handed her senior debut in a 6-0 friendly win over Northern Ireland in February 2021.
She was also part of Team GB’s women’s football squad for the delayed 2020 Tokyo Olympic Games alongside City’s Ellie Roebuck and Karen Bardsley.
Head Coach Gareth Taylor added: “We’re so pleased to have been able to bring Sandy back to City – over the past few seasons, she has worked incredibly hard to establish herself as one of English football’s top goalkeepers.
“She is a player I’ve admired for a long time, but especially during my time in charge of the team so far – whenever we’ve come up against her, she has shown just what a talent she is.
“Whether it be for club or country, her dedication and commitment to her craft is clear to see and to have her and her fellow England compatriot in Ellie [Roebuck] working together and competing for that number one spot on a daily basis will be massively beneficial for both players.
“She has a very bright future ahead of her though and we’re excited to be on this journey alongside her over the coming years.”